Contact lenses

Abstract

The invention provides silicone hydrogel contact lenses that exhibit reduced back surface debris and reduced incidence of superior epithelial arcurate lesions.

Description

FIELD OF THE INVENTIONThe present invention relates to contact lenses. In particular, the invention provides silicone hydrogel contact lenses that exhibit reduced back surface debris and a reduced incidence of superior epithelial arcurate lesions.BACKGROUND OF THE INVENTIONThe use of contact lenses for reasons of cosmetics and for the correction of visual acuity is well known. However, use of contact lenses is known to result in the development of either or both superior epithelial arcuate lesions and superior arcuate staining. Additionally, debris such as mucin balls, cellular debris, lint, dust, bubbles, make-up, or the like (“back-trapped debris”) may become trapped between the back surface of the lens and the eye. These problems have been found across the range of conventional soft contact lenses, but are found to be substantially more prevalent in the high oxygen permeability silicone hydrogel contact lenses introduced into the market within the last several years. Thus, a need...

AI Technical Summary

Benefits of technology

It is a discovery of the invention that by maintaining the center and lenticular junction stiffnesses and the advancing contact angle of a lens at certain levels, the incidence of SEALs, meaning superior arcuate lesions and superior arcuate staining of about grade 2 or higher, and back-trapped debris may be significantly reduced or substantially eliminated. By “grade 2” staining is meant that small aggregates, or groupings, of corneal epithelial cell loss are visible using sodium fluorescein. By “significantly reduced” means that SEALs are reduced to an incidence of about 1 percent or less and that less than about 35 percent of lens wearers experience no back-trapped debris or only a mild amount, meaning an easily visible amount on slit lamp examination at a magnification of about 16 to about 20×, but which amount is not clinically significant.

Problems solved by technology

However, use of contact lenses is known to result in the development of either or both superior epithelial arcuate lesions and superior arcuate staining.

Additionally, debris such as mucin balls, cellular debris, lint, dust, bubbles, make-up, or the like (“back-trapped debris”) may become trapped between the back surface of the lens and the eye.

These problems have been found across the range of conventional soft contact lenses, but are found to be substantially more prevalent in the high oxygen permeability silicone hydrogel contact lenses introduced into the market within the last several years.

Images